First Fall Freeze

Cold weather has finally arrived in Southeastern North Carolina.  The first freeze of the season took our temperature down to 27 degrees in my backyard yesterday morning, with 29 degrees recorded at the nearby Wilmington airport.  Here's a graphic I made at work yesterday showing the end of the growing season in Wilmington and some statistics for the 2012 growing season:

2012 Growing Season statistics for a portion of eastern North and South Carolina served by the NWS office in Wilmington, NC.

This freeze spelled the bitter end of all of my summer vegetables and herbs including the peppers, tomatoes and basil.  I've saved plenty of seeds from all of these to replant next spring.

The leaves and flowers on our backyard Lantana bushes were killed as always happens with the first fall freeze.  The remainder of the plant is much more cold-hardy and will spring back to life next year.  Roots of these lantana bushes have survived at least 15 degree air temperatures back in 2002 and then successfully resprouted the following spring.

Lantana, before and after the freeze

A freeze-damaged limb on an Owari Satsuma. 

Soil temperatures have been steadily falling for the past couple of months.  Once soil temperatures fall below 55 degrees Fahrenheit, dormancy develops in all of my citrus trees.  Winter dormancy is actually a very good thing since it gives citrus trees the ability to survive moderate freezes with no damage to their leaves or branches.  An actively growing "awake" citrus tree will sustain heavy damage with air temperatures in the upper 20s; yesterday morning's 27 degree low temperature froze only a tiny amount of late, tender growth on the outermost branches.  I try to prevent my citrus from producing new growth late in the year by not applying fertilizer after the end of June.





I wish I could grow edible bananas here.  I've experimented with several banana varieties reputed to be cold-hardy including Misi Luki, Red Iholene, Ice Cream, Dwarf Cavendish, and Williams.  None of those varieties survived the cold winter of 2010-2011 which literally froze the top few inches of soil in my backyard -- something I never thought could happen here.  The only banana variety that did survive the mayhem is Musa ornata, an ornamental variety that continues to reliably produces beautiful flowers each summer.  The flowers yield small green bananas along a long stalk during the summer and early fall, but given the limitations of our climate they never grow to more than 4 or 5 inches in length with a diameter around 3/4 inch.  Bananas also become dormant with cooler fall temperatures, although unlike citrus they cannot develop an ability to sustain sub-freezing temperatures even in their dormant state.

Musa ornata bananas in my backyard during mid-summer (left) and after our recent hard freeze (right).
The underground corm is now dormant and will sprout new banana plants next spring.